Compressed air operable starter for internal combustion engines



May 11, 1965 H. HECKT 3,182,650 COMPRESSED AIR OPERABLE STARTER FOR INTERNAL COMBUSTION ENGINES Filed June 8, 1962 2 Sheets-Sheet 1 mwwra/e H. HECKT 3,182,650 OPERAB STARTER FOR INTERNAL OMBUST ENGINES May 11, 1965 COMPRESSED AIR 2 Shuets-Sheet 2 Filed June 8, 1962 IN VENTOQ A e/nz fleckf United States Patent M 3,182,650 COMPRESSED AIR OPERABLE STARTER FUR INTERNAL COMBUSTION ENGINES Heinz Heckt, Sprocldiovel, Westphalia, Germany, assignor to G. Diisterloh, Fabrik fiir Bergwerksbedarf G.rn.b.H., Sprockhovel, Westphalia, Germany Filed June 8, 1962, Ser. No. 201,084 Claims priority, appiicatigr germany, June 12, 1961,

5 6 Claims. (Cl. 123179) The present invention relates to a compressed air operable starter for internal combustion engines, especially diesel engines, in which the control valve is arranged on the starter housing and is operable manually or pneumatically directly or by remote control.

In order to assure a proper operation of a compressed air operable starter for internal combustion engines, it is of importance that the starter pinion will at slow rotation be introduced into the rim face of the internal combustion engine and that the main valve will be opened only when the pinion has reached its end position whereby the nominal speed of the starter will be obtained. After the internal combustion engine has started, it is important to bring the pinion out of mesh in a reliable manner.

With the heretofore known compressed air operable starters, the starting operation is to a major extent dependent on the operation of the person actuating the starter. This is due to the fact that the starting operation has two phases which are to be initiated by the operator. With the heretofore known arrangements, by tilting a manually operable lever into a first position, the pinion is brought into mesh with the gear to be actuated thereby, and subsequently the lever is moved into a second position for initiating the starting operation proper while in said second phase the supply of compressed air is fully opened. While these two lever positions are separated from each other by abutments, it is nevertheless possible to skip the first position and to place the lever at once into the second position which then in most instances will cause disturbances. After the internal combustion engine has started, the operator has immediately to return the lever into its starting position whereupon the pinion due to a spring force will be disengaged from its respective gear.

The above mentioned two-phase starting operation which has to be carried out by the operator has various drawbacks. Thus, for instance, if the starting lever is moved too fast into its second position, the pinion will immediately at full speed engage the gear to be driven thereby with the result that damage especially to the pinion and the gear to be driven thereby will be unavoidable. Moreover, a premature wear of the overload clutch of the starter is unavoidable when the operator after the ignition speed has been obtained, does not bring about a fast disengagement of the pinion. If the pinion is not quickly enough disengaged from the gear to be driven thereby, the gear will overtake the pinion as to speed, and the spring force will, due to the increased tooth flank pressure, be insufficient to disengage the pinion.

Furthermore, with the heretofore known controls for the compressed air operable starter, especially with larger starter types, a considerable effort is required in order to shift the operating lever during the starting operation from the first to the second position. This is due to the fact that the main valve acted upon by compressed air has to be lifted off from its valve seat. a

It is, therefore, an object of the present invention to provide a compressed air operable starter for internal combustion engines, in which the control is such that the starting operation, i.e. the engagement of the pinion and the subsequent starting operation proper, will, following a 3,182,650 Patented May 11, 1965 single easily effected control movement of a corresponding control member be efliected automatically.

t is a further object of this invention to provide a starter as set forth in the preceding paragraph, which will bring about that the disengagement of the pinion will be eifected automatically and, as the case may be, at an increased force.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

FIG. 1 is a side view of a compressed air operable starter partially in section and partially in view.

FIG. 2 is a section taken along the line 11-11 of FIG. 1.

FIG. 3 illustrates the electric diagram for an electropneumatic actuation of the control valve by means of a contact tachometer.

An essential feature of the present invention consists in that the manually or pneumatically operable control valve, when in working position, establishes communication on one hand between the cylinder chamber of an engaging piston by means of which the driving pinion is brought into its engaging position, and on the other hand establishes communication between a nozzle leading to the rotors of the starter and a compressed air supply conduit while through said nozzle a small quantity of the cornpressed air passes for starting the starter. The establishment of said communication is such that the said engaging piston will, only after the pinion is completely engaged, free the path for the full supply of compressed air to the rotors, and that in the rest position of the control valve the engaging piston actuated by compressed air will in combination with a spring force hold the driving pinion out of engagement.

According to a further feature of the present invention, the engaging piston, when in operative position, holds a venting valve in its open position by means of which a spring loaded main valve will be controlled for freeing the full compressed air supply to the rotors.

In order to speed up the engagement of the pinion, it is provided according to the present invention that during the return of the control valve into its rest position, the engaging piston will be actuated by compressed air whereby in combination with the spring force acting upon the pinion in a disengaging sense, an additional force will disengage said pinion.

According to an expedient further development of the invention, with a pneumatic actuation of a control valve, a contact tachometer is provided which, when the ignition speed of the internal combustion engine has been reached, will actuate an electropneumatic shifting valve by means of which the supply of compressed air to the control valve is cut olf and the latter is vented so that the control valve will under the action of the spring force return to its starting position.

The design of the control according to the invention has over heretofore known arrangements of the type involved the advantage that the operator after having shifted the operating lever into a single position cannot any longer influence the starting operation in an unfavorable manner. Due to the employment of a contact tachometer, an automatic disengagement of the pinion will be obtained as soon as the internal combustion engine opcrates at ignition speed so that also in this respect no disturbances can be caused by any mistake in the operation.

Referring now to the drawings in detail, the compressed air operable starter shown therein comprise primarily a housing 1 with compressed air operable rotors 2 therein arranged adjacent to each other. These rotors 2 convey their rotary movement through an interposed transmission (not shown) to a pinion 3 and to control members arranged in part in the starter housing 1 and e) in part in an additional housing 4 connected to the housing 1. Only a portion of the gear ring 5 of the internal combustion engine is shown.

The above mentioned control members comprise an engaging or control piston 6 which is reciprocably mounted in the starter housing 1 and has connected thereto a piston rod 7 extending to both sides of said piston 6. One end of the piston rod 7 is connected to one end of a twoarm lever 8 the other end of which is linked to the pinion 3 by a slide member 31. The additional housing 4 houses the drive or control valve 0 which consists primarily of a displaceably mounted control spool 9 and a pressure spring 10 tending to maintain said control spool 9 in its rest position. If the actuation of the control valve is effected by hand, the control spool 9 has connected thereto a pulling element as for instance a Bowden wire 11 which leads to an actuating lever 12.

The connection with the compressed air supply line is effected at the connection 13 from where a passage 14 branches off on one hand to the drive or control valve c and on the other hand to a venting valve 15. The venting valve 15 is held in closing position by a spring 16 as long as the piston 6 occupies its rest position. In the extension of the connection 13 there is provided the main valve 17 which, when occupying its open position, frees the passage for the full compressed air supply to the rotors. The main valve 17 is through the intervention of a valve rod 18 connected to a piston 19 which is displaceably guided in a cylinder chamber 20 between two end positions. Main valve 17 is continuously urged into closing position by a spring 21 resting against piston 19.

In rest condition, the compressed air acting at the connection 13 passes through passage 14 and branch conduit 22 into the cylinder chamber of the drive valve 0. From here there exists a connection to the cylinder chamber of piston 6 through passage 23, piston 6 being held in its rest position due to the compressed air acting thereon. When valve spool 9, for instance by manual actuation, is moved into its working position, the compressed air passes from the housing of the drive valve c through passage 24 into the front portion of the cylinder chamber of piston 6. At the same time, the rear portion of the cylinder chamber is connected with a venting conduit 25 through passage 23.

With the entrance of compressed air into the front portion of the cylinder chamber pertaining to piston 6, a small quantity of compressed air passes through a nozzle 26 to the rotors 2 and imparts upon the same a slow rotary movement. The piston 6 will under the influence of the entering compressed air move from its left-hand end position shown in FIG. 1 into its right-hand end position while pinion 3 will be moved into its meshing position through the intervention of the two-arm lever 8 and the sliding member 31. As soon as the piston 6 has reached its working position, the rear end of the piston rod 7 opens the venting valve 15 whereby compressed air passes through a further conduit 27 into the cylinder chamber of piston 19. As a result thereof, piston 19 will under the influence of compressed air move against the thrust of spring 21 from its left-hand position shown in FIG. 1 into its right-hand end position while opening the main valve 17 so that compressed air will in full quantity and force flow to the rotors 2 and impart upon the same the nominal rotary speed.

When by manual operation the operating lever 12 is returned to its starting position after the combustion engine has started, compressed air will again through passage 23 pass into the rear portion of the cylinder chamber pertaining to spool 6 whereby the latter is pressed back into its starting position, and pinion 3 is disengagedr When the control of the valve 0 is effected pneumatically, a compressed air operable valve 28 is provided for actuation of the starter. If this valve 23 is opened, compressed air passes through conduits 29 and 39 into a cylin- 4 der chamber of the valve 0 and moves the valve spool 9 into its working position whereupon the same starting cycle will follow as has been described in connection with the actuation of the drive valve by means of a pulling element or the like.

The control diagram of FIG. 3 illustrates a fully automatic control of the compressed air operable starter by means of a tachometer. In this instance an electropneumatic shift valve 33 is provided for controlling the drive valve 0. The electromagnet 41 of said valve 33 receives current through a circuit 35 by means of a pushbutton switch 36 from a battery 34. The circuit 35 is additionally passed through a normally closed switch having a movable blade 42 which is under the control of the tachometer 32 arranged on the combustion engine 40. When the push-button 36 is closed, the electromagnet 41 shifts over the shift valve 33 and thereby frees the path for the compressed air from main conduit 37 through conduits 38 and 39. Subsequently, the starting operation will be effected in the same manner as described above, namely by direct mechanical or pneumatic operation of the drive valve.

As soon as the internal combustion engine has reached its ignition speed, the tachometer 32 reacts and opens the circuit 35 of valve 33 by opening switch blade 42. As a result thereof, the supply line for compressed air to the drive valve c is shut off and valve c is at the same time vented through conduit 39 so that the valve spool 9 will due to spring 10 acting thereupon be returned into its starting position. Inasmuch as the tachometer will interrupt the circuit 35 only after the engine has reached its ignition speed and, since the tachometer will, during its entire running period, maintain the circuit interrupted, a too slow actuation of the push-button switch 36 cannot prevent the properly timed disengagement of the pinion. Moreover, when the engine is running, a renewed and, as the case may be unintentional actuation of the pushbutton switch 36 cannot actuate the starter again. The combination of the normally closed switch and the engine driven tachometer controlling the switch thus forms means responsive to the speed of the engine, or the speed of the pinion when it is engaged with the engine ring for automatically retracting the pinion from the ring gear.

It is, of course, to be understood that the present invention is, by no means, limited to the particular construction shown in the drawings but also comprises any modifications within the scope of the appended claims.

What I claim is:

l. A fluid pressure operable starter for internal combustion engines, especially Diesel engines, which comprises: a housing, a pinion at one end of the housing movable axially from an ineffective position into an effective position for engagement with gear means of the engine to be started and vice versa, fluid pressure operable pinion control piston means in the housing operatively connected to said pinion and having first surface means adapted to be acted upon by fluid pressure for moving said pinion from its ineffective into its effective position, said pinion control piston means also having second surface means adapted to be acted upon by fluid pressure for moving said pinion from its effective into its ineffective position, fluid operable rotor means in said housing rotatably connected to said pinion means for rotating the same, restricted passage means establishing a restricted communication only between said first surface means and said rotor means for admitting only a restricted fluid pressure to said rotor means to rotate the latter and thereby said pinion at a minimum speed, and control means including a first valve operable to admit pressure fluid selectively to said first surface means and said second surface means, said control means also including a second valve operable to admit full fluid pressure to said rotor means and means responsive to said pinion reaching its effective position for actuating said second valve to admit full fluid pressure to said rotor means for rotating the same at full speed.

2. A fluid pressure operable starter for internal combustion engines, especially Diesel engines, which comprises: a pinion movable from an ineffective position into an effective position for engagement with gear means of the engine to be started and vice versa, fluid pressure operable pinion control piston means operatively connected to said pinion and having first surface means adapted to be acted upon by fluid pressure for moving said pinion from its ineffective position into its effective position, said pinion control piston means also having second surface means adapted to be acted upon by fluid pressure for moving said pinion from its effective into its ineffective position, fluid operable rotor means rotatably connected to said pinion means for rotating the same, restricted passage means establishing a restricted communication only between said first surface means and said rotor means for admitting only a restricted fluid pressure to said rotor means to rotate the latter and thereby said pinion at a minimum speed, and control means operable to admit pressure fluid selectively to said first surface means and said second surface means, said control means including pressure fluid operable main valve means normally preventing full fluid pressure from being conveyed to said rotor means, said control means also including auxiliary valve means operatively connected to said main valve means and responsive to said pinion reaching its effective position to convey fluid pressure to said main valve means to move the latter into position for admitting full fluid pressure to said rotor means.

3. A fluid pressure operable starter for internal combustion engines, especially Diesel engines, which comprises: a pinion movable from an ineffective position into an effective position for engagement with gear means of the engine to be started and vice versa, fluid pressure operable pinion control piston means operatively connected to said pinion and having first surface means adapted to be acted upon by fluid pressure for moving said pinion from its ineffective into its effective position, said pinion control piston means also having second surface means adapted to be acted upon by fluid pressure for moving said pinion from its effective into its ineffective position, fluid operable rotor means rotatably connected to said pinion means for rotating the same, restricted passage means establishing a restricted communication only between said first surface means and said rotor means for admitting only a restricted fluid pressure to said rotor means to rotate the latter and thereby said pinion at a minimum speed, and control means including valve spool means for selectively admitting pressure fluid to said first surface means and to said second surface means, spring means continuously urging said valve spool means into position for admitting pressure fluid to said second surface means, said control means also including means responsive to said pinion reaching its effective position to admit full fluid pressure to said rotor means for rotating the same at full speed.

4. A starter according to claim 1, in which said housing comprises a cylinder chamber arranged adjacent to and above said rotor means and in which said pinion control piston means is located, and means extending laterally from said piston means to said pinion and operatively interconnecting the same.

5. A starter according to claim 3, which includes means for manually operating said valve spool means.

6. A fluid pressure operable starter for internal combustion engines, especially Diesel engines, which comprises: a pinion movable from an ineffective position into an effective position for engagement with gear means of the engine to be started and vice versa, fluid pressure operable pinion control piston means operatively connected to said pinion and having first surface means adapted to be acted upon by fluid pressure for moving said pinion from its ineffective into its effective position, said pinion control piston means also having second surfact means adapted to be acted upon by fluid pressure for moving said pinion from its effective into its ineffective position, fluid operable rotor means rotatably connccted to said pinion means for rotating the same, restricted passage means establishing a restricted communication only between said first surface means and said rotor means for admitting only a restricted fluid pressure to said rotor means to rotate the latter and thereby said pinion at a minimum speed, control means operable to admit pressure fluid selectively to said first surface means and said second surface means, said control means including means responsive to said pinion reaching its effective position to admit full fluid pressure to said rotor means for rotating the same at full speed, and means responsive to a predetermined speed rotation of said pinion when the pinion is in its effective position for automatically bringing about movement of said pinion to its ineffective position.

References Cited by the Examiner UNITED STATES PATENTS Re. 13,681 1/14 Stuller 91-31 2,608,966 9/52 Jenny 9131 2,653,577 9/53 Jenny 91-53 FOREIGN PATENTS 574,901 4/ 33 Germany.

RICHARD B. WILKINSON, Primary Examiner. 

1. A FLUID PRESSURE OPERABLE STARTER FOR INTERNAL COMBUSTION ENGINES, ESPECIALLY DIESEL ENGINES, WHICH COMPRISES: A HOUSING, A PINION AT ONE END OF THE HOUSING MOVABLE AXIALLY FROM AN INEFFECTIVE POSITION INTO AN EFFECTIVE POSITION FOR ENGAGEMENT WITH GEAR MEANS OF THE ENGINE TO BE STARTED AND VICE VERSA, FLUID PRESSURE OPERABLE PINION CONTROL PISTON MEANS IN THE HOUSING OPERATIVELY CONNECTED TO SAID PINION AND HAVING FIRST SURFACE MEANS ADAPTED TO BE ACTED UPON BY FLUID PRESSURE FOR MOVING SAID PINION FROM ITS INEFFECTIVE INTO ITS EFFECTIVE POSITION, SAID PINION CONTROL PISTON MEANS ALSO HAVING SECOND SURFACE MEANS ADAPTED TO BE ACTED UPON BY FLUID PRESSURE FOR MOVING SAID PINION FROM ITS EFFECTIVE INTO ITS INEFFECTIVE POSITION, FLUID OPERABLE ROTOR MEANS AND IN SAID HOUSING ROTATABLY CONNECTED TO SAID PINION MEANS FOR ROTATING THE SAME, RESTRICTED PASSAGE MEANS ESTABLISHING A RESTRICTED COMMUNICATION ONLY BETWEEN SAID FIRST SURFACE MEANS AND SAID ROTOR MEANS FOR ADMITTING ONLY A RESTRICTED FLUID PRESSURE TO SAID ROTOR MEANS TO ROTATE THE LATTER AND THEREBY SAID PINION AT A MINIMUM SPEED, AND CONTROL MEANS INCLUDING A FIRST VALVE OPERABLE TO ADMIT PRESSURE FLUID SELECTIVELY TO SAID FIRST SURFACE MEANS AND SAID SECOND SIRFACE MEANS, SAID CONTROL MEANS ALSO INCLUDING A SECOND VALVE OPERABLE TO ADMIT FULL FLUID PRESSURE TO SAID ROTOR MEANS AND MEANS RESPONSIVE TO SAID PINION REACHING ITS EFFECTIVE POSITION FOR ACTUATING SAID SECOND VALVE TO ADMIT FULL FLUID PRESSURE TO SAID ROTOR MEANS FOR ROTATING THE SAME AT FULL SPEED. 